1 | // SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause) |
2 | /* |
3 | * Driver for the onsemi 10BASE-T1S NCN26000 PHYs family. |
4 | * |
5 | * Copyright 2022 onsemi |
6 | */ |
7 | #include <linux/kernel.h> |
8 | #include <linux/bitfield.h> |
9 | #include <linux/errno.h> |
10 | #include <linux/init.h> |
11 | #include <linux/module.h> |
12 | #include <linux/mii.h> |
13 | #include <linux/phy.h> |
14 | |
15 | #include "mdio-open-alliance.h" |
16 | |
17 | #define PHY_ID_NCN26000 0x180FF5A1 |
18 | |
19 | #define NCN26000_REG_IRQ_CTL 16 |
20 | #define NCN26000_REG_IRQ_STATUS 17 |
21 | |
22 | // the NCN26000 maps link_ctrl to BMCR_ANENABLE |
23 | #define NCN26000_BCMR_LINK_CTRL_BIT BMCR_ANENABLE |
24 | |
25 | // the NCN26000 maps link_status to BMSR_ANEGCOMPLETE |
26 | #define NCN26000_BMSR_LINK_STATUS_BIT BMSR_ANEGCOMPLETE |
27 | |
28 | #define NCN26000_IRQ_LINKST_BIT BIT(0) |
29 | #define NCN26000_IRQ_PLCAST_BIT BIT(1) |
30 | #define NCN26000_IRQ_LJABBER_BIT BIT(2) |
31 | #define NCN26000_IRQ_RJABBER_BIT BIT(3) |
32 | #define NCN26000_IRQ_PLCAREC_BIT BIT(4) |
33 | #define NCN26000_IRQ_PHYSCOL_BIT BIT(5) |
34 | #define NCN26000_IRQ_RESET_BIT BIT(15) |
35 | |
36 | #define TO_TMR_DEFAULT 32 |
37 | |
38 | static int ncn26000_config_init(struct phy_device *phydev) |
39 | { |
40 | /* HW bug workaround: the default value of the PLCA TO_TIMER should be |
41 | * 32, where the current version of NCN26000 reports 24. This will be |
42 | * fixed in future PHY versions. For the time being, we force the |
43 | * correct default here. |
44 | */ |
45 | return phy_write_mmd(phydev, MDIO_MMD_VEND2, MDIO_OATC14_PLCA_TOTMR, |
46 | TO_TMR_DEFAULT); |
47 | } |
48 | |
49 | static int ncn26000_config_aneg(struct phy_device *phydev) |
50 | { |
51 | /* Note: the NCN26000 supports only P2MP link mode. Therefore, AN is not |
52 | * supported. However, this function is invoked by phylib to enable the |
53 | * PHY, regardless of the AN support. |
54 | */ |
55 | phydev->mdix_ctrl = ETH_TP_MDI_AUTO; |
56 | phydev->mdix = ETH_TP_MDI; |
57 | |
58 | // bring up the link |
59 | return phy_write(phydev, MII_BMCR, NCN26000_BCMR_LINK_CTRL_BIT); |
60 | } |
61 | |
62 | static int ncn26000_read_status(struct phy_device *phydev) |
63 | { |
64 | /* The NCN26000 reports NCN26000_LINK_STATUS_BIT if the link status of |
65 | * the PHY is up. It further reports the logical AND of the link status |
66 | * and the PLCA status in the BMSR_LSTATUS bit. |
67 | */ |
68 | int ret; |
69 | |
70 | /* The link state is latched low so that momentary link |
71 | * drops can be detected. Do not double-read the status |
72 | * in polling mode to detect such short link drops except |
73 | * the link was already down. |
74 | */ |
75 | if (!phy_polling_mode(phydev) || !phydev->link) { |
76 | ret = phy_read(phydev, MII_BMSR); |
77 | if (ret < 0) |
78 | return ret; |
79 | else if (ret & NCN26000_BMSR_LINK_STATUS_BIT) |
80 | goto upd_link; |
81 | } |
82 | |
83 | ret = phy_read(phydev, MII_BMSR); |
84 | if (ret < 0) |
85 | return ret; |
86 | |
87 | upd_link: |
88 | // update link status |
89 | if (ret & NCN26000_BMSR_LINK_STATUS_BIT) { |
90 | phydev->link = 1; |
91 | phydev->pause = 0; |
92 | phydev->duplex = DUPLEX_HALF; |
93 | phydev->speed = SPEED_10; |
94 | } else { |
95 | phydev->link = 0; |
96 | phydev->duplex = DUPLEX_UNKNOWN; |
97 | phydev->speed = SPEED_UNKNOWN; |
98 | } |
99 | |
100 | return 0; |
101 | } |
102 | |
103 | static irqreturn_t ncn26000_handle_interrupt(struct phy_device *phydev) |
104 | { |
105 | int ret; |
106 | |
107 | // read and aknowledge the IRQ status register |
108 | ret = phy_read(phydev, NCN26000_REG_IRQ_STATUS); |
109 | |
110 | // check only link status changes |
111 | if (ret < 0 || (ret & NCN26000_REG_IRQ_STATUS) == 0) |
112 | return IRQ_NONE; |
113 | |
114 | phy_trigger_machine(phydev); |
115 | return IRQ_HANDLED; |
116 | } |
117 | |
118 | static int ncn26000_config_intr(struct phy_device *phydev) |
119 | { |
120 | int ret; |
121 | u16 irqe; |
122 | |
123 | if (phydev->interrupts == PHY_INTERRUPT_ENABLED) { |
124 | // acknowledge IRQs |
125 | ret = phy_read(phydev, NCN26000_REG_IRQ_STATUS); |
126 | if (ret < 0) |
127 | return ret; |
128 | |
129 | // get link status notifications |
130 | irqe = NCN26000_IRQ_LINKST_BIT; |
131 | } else { |
132 | // disable all IRQs |
133 | irqe = 0; |
134 | } |
135 | |
136 | ret = phy_write(phydev, NCN26000_REG_IRQ_CTL, val: irqe); |
137 | if (ret != 0) |
138 | return ret; |
139 | |
140 | return 0; |
141 | } |
142 | |
143 | static struct phy_driver ncn26000_driver[] = { |
144 | { |
145 | PHY_ID_MATCH_MODEL(PHY_ID_NCN26000), |
146 | .name = "NCN26000" , |
147 | .features = PHY_BASIC_T1S_P2MP_FEATURES, |
148 | .config_init = ncn26000_config_init, |
149 | .config_intr = ncn26000_config_intr, |
150 | .config_aneg = ncn26000_config_aneg, |
151 | .read_status = ncn26000_read_status, |
152 | .handle_interrupt = ncn26000_handle_interrupt, |
153 | .get_plca_cfg = genphy_c45_plca_get_cfg, |
154 | .set_plca_cfg = genphy_c45_plca_set_cfg, |
155 | .get_plca_status = genphy_c45_plca_get_status, |
156 | .soft_reset = genphy_soft_reset, |
157 | }, |
158 | }; |
159 | |
160 | module_phy_driver(ncn26000_driver); |
161 | |
162 | static struct mdio_device_id __maybe_unused ncn26000_tbl[] = { |
163 | { PHY_ID_MATCH_MODEL(PHY_ID_NCN26000) }, |
164 | { } |
165 | }; |
166 | |
167 | MODULE_DEVICE_TABLE(mdio, ncn26000_tbl); |
168 | |
169 | MODULE_AUTHOR("Piergiorgio Beruto" ); |
170 | MODULE_DESCRIPTION("onsemi 10BASE-T1S PHY driver" ); |
171 | MODULE_LICENSE("Dual BSD/GPL" ); |
172 | |